The invention relates to a group transmission device, in particular for commercial vehicles, including a main group with a central synchronizing unit for synchronizing at least two main group shifting units and an auxiliary group with an auxiliary group shifting unit.
A group transmission device is already known from DE 101 52 857 A1; this comprises a main group with a central synchronizing unit for synchronizing main group shifting units for changing a main group ratio, an auxiliary group with auxiliary group shifting units for changing an auxiliary group ratio and an open- and/or closed-loop control unit which is provided to actuate in a shifting operation the auxiliary group shifting units and the central synchronizing unit in order to change an overall gear ratio.
It is the principal object of the invention to provide a group transmission arrangement with shortened gear change times so as to facilitate up-shifting during vehicle acceleration and downshifting particularly during hill climbing.